Welding wire feeder method

ABSTRACT

A wire feeder device and method for feeding a welding wire includes a plurality of first and second gripper members movable from an open position to a closed position to engage on another and the welding wire along an engagement path. A projection from each gripping member is received in a recess defined in its engaged gripping member such that the welding wire is contacted on opposite sides in notches defined at the distal edges of respective projections. The gripper members may include a built-in centering function to center a position of the welding wire, may be made at least partially of material that conforms to the welding wire, and may be biased toward one another to firmly grip the welding wire.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional application of, and claims priorityfrom, U.S. patent application Ser. No. 15/668,014 filed Aug. 3, 2017 andentitled “Welding Wire Feeder Device”.

FIELD OF THE DISCLOSURE

Embodiments of the present disclosure relate generally to welding wirefeeders and methods and, in particular, to a caterpillar style wirefeeder and method.

BACKGROUND OF THE DISCLOSURE

Welding is a widely known process. Generally speaking, welding may beperformed manually or, in some applications, it may be automated.Welding operations rely on a variety of types of equipment to ensure thesupply of welding consumables (e.g., wire feed, shielding gas, etc.) isprovided to the weld joint in an appropriate amount at the desired time.For example, a wire feeder is often used to provide welding wire at adesired feed rate to a welding torch.

Wire feeders facilitate the feeding of welding wire from a wire spool ordrum to a welding torch at a desired wire feed rate. In general, priorart wire feeders incorporate at least one pair of rotating wire feedrollers to feed the wire. In these systems, the needed pulling frictionbetween the rollers and the wire may be created by using one or bothrollers to apply a squeezing pressure to the wire between the pair ofrollers. In addition, some known wire feeders have grooves formed in oneor both rollers to maintain the wire in position and/or to enhance orcontrol the frictional forces between the wire and rollers.

Wire feeders of the type described above have a number of shortcomings.For example, long set up times are common as a user typically needs toopen an access panel, and then open the feed mechanism to initiallythread the wire through the wire feeder. In addition, the user oftenneeds to change the rollers and wire guides when switching betweenwelding wires of different diameters. In addition to the time it takesto switch the rollers/guides, this also introduces the possibility thatthe user may use the wrong set of rollers and/or guides. The user mayalso need to adjust the pressure of the feed rollers, which introducesthe possibility that the user may incorrectly set the roller pressure,resulting in an undesirably high degree of wire deformation due to thehigh pressure. In addition, the mechanism may become clogged as a resultof a peeled wire caused by too much pressure and/or nonalignment in themechanism, and unreliable feeding of the wire due to wire slippage(contact point friction). Further, safety issues (e.g., finger pinchingand the like) may be a concern as a user accesses and opens themechanism. Furthermore, prior art wire feeders that rely on a pair ofrotating rollers generally require a high level of maintenance, whichresults in high maintenance costs associated with buying and stockingspare parts, and which increases the potential for improper maintenancepractices.

One solution that has been used to overcome some of these shortcomings,has been to incorporate a second pair of rotating rollers immediatelyafter the first pair of rotating rollers. In use, movement of the firstand second pair of rotating rollers is synchronized. By adding a secondpair of rollers, the relatively high surface pressure on the wire may behalved. Unfortunately, adding a second pair of rollers often creates newissues. For example, with the introduction of a second pair of rollers,an increased risk exists for tangling of the wire, especially betweenthe two pairs of rotating rollers. Also there is an increased risk of“shaving,” which is the tearing-away of material from the surface of thewire due to misalignment between the grooves formed in the rotatingrollers and associated nozzles, and due to slipping of the wire relativeto the rotating rollers. This can increase the possibility of cloggingof the feed mechanism, the torch cable liner, and the torch.

In view of the foregoing, it would be desirable to provide a wire feederdevice for welding that overcomes the shortcomings associated with priorart devices.

SUMMARY OF THE DISCLOSURE

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended asan aid in determining the scope of the claimed subject matter.

Various embodiments of the present disclosure are generally directed toa wire feeder device. One exemplary embodiment of the wire feeder devicefor feeding a welding wire in a feeding direction from an input end toan output end may include at least one gripper assembly for contactingand feeding the welding wire. The gripper assembling includes a rollerchain, and first and second sprockets operatively coupled to the rollerchain so that rotation of the first and second sprockets causes theroller chain to rotate, and a plurality of first and second grippermembers. The first and second gripper members are positioned on oppositesides of the welding wire and are movable from an open position to aclosed position to contact and grip the welding wire. The first andsecond gripper members are longitudinally movable along a substantiallylinear path with the rotating roller chain so that the welding wire ismoved from the input end to the output end.

The first and second gripper members may include a centering feature topositionally center the welding wire substantially parallel to thesubstantially linear path of the first and second gripper members. Thefirst and second gripper members may each include a projection and acutout, the projection of the first gripper member being receivablewithin the cutout of the second gripper member, and the projection ofthe second gripper member being receivable within the cutout of thefirst gripper member. The projections may include convergingtransversely sloped surfaces that angle from a high point adjacent anouter side surface of the gripper member to a lower point or nadiradjacent a centerline of the gripper member. Each of the projections mayinclude a notch at the nadir for contacting an outer surface of thewelding wire. The notch may have an arcuate, typically semi-circularshape. Since the projection of each gripper member is received in thecutout of the other gripper member, the notches formed in first andsecond gripper members are longitudinally offset such that they contactthe welding wire at different but longitudinally adjacent points alongthe wire. This offset minimizes compression and potential distortion ofthe welding wire. The first and second gripper members may be made froma flexible material. Each gripper member may include a spring or otherbiasing member for biasing the first and second gripper memberstransversely of the welding wire to the closed position.

The roller chain may include a plurality of individual chain linkscoupled to one another. Each of the plurality of first and secondgripper members may have a length in the direction of wire movementsubstantially corresponding to the length of an individual chain link toprovide an increased contact area between the first and second grippermembers and the welding wire. Rotation of the roller chain causes thefirst and second gripper members to move from the open position to theclosed position, and subsequently from the closed position to the openposition.

The aforesaid at least one gripper assembly may be first and secondgripper assemblies. The first plurality of gripper members may becoupled to the roller chain of the first gripper assembly while thesecond plurality of gripper members may be coupled to the roller chainof the second gripper assembly. The first and second gripper assembliesmay be orientated coplanar with respect to one another (i.e., verticallyadjacent one another). In use, the respective roller chains of the firstand second gripper assemblies may be configured to rotate in oppositedirections such that the gripper assemblies move along a substantiallylongitudinal path in the same direction at their engaged portions toeffect a pulling action on the welding wire. In this arrangement thefirst and second gripper members located on the first and second gripperassemblies, respectively, move vertically from the open position to theclosed position adjacent the input end of the assembly, and the firstand second gripper assemblies move from the closed position to the openposition adjacent the output end of the assembly. Moving the first andsecond gripper members from the open position to the closed positioncauses the first and second gripper members to grip the welding wiretherebetween so that the welding wire is movable, i.e., pulled, from theinput end to the output end.

The roller chain of the first gripper assembly and the roller chain ofthe second gripper assembly may each include a plurality of individualchain links coupled to one another, each of the first and second grippermembers having a size substantially corresponding to the size of eachindividual link so that one of the plurality of first gripper memberscan be coupled to a corresponding one of the individual links of theroller chain of the first gripper assembly, and so that one of theplurality of second gripper members can be coupled to a correspondingone of the individual links of the roller chain of the second gripperassembly. The first and second gripper members may each include abiasing member for supplying a biasing force away from each individuallink coupled thereto.

The at least one gripper assembly may alternatively be a single gripperassembly. The roller chain may include a plurality of individual chainlinks coupled to one another to form a chain, each individual link ofthe roller chain be associated with one of the plurality of firstgripper members and one of the plurality of second gripper members. Thefirst and second gripper members may be disposed in adjacent planes,i.e., laterally, rather than vertically, adjacent, or orientated in aside-by-side relationship on each individual link. In use, rotation ofthe roller chain causes the first and second gripper members to movelaterally from the open position to the closed position, andsubsequently from the closed position to the open position. Moving thefirst and second gripper members from the open position to the closedposition causes the first and second gripper members to grip the weldingwire therebetween in the manner described above, the first and secondgripper members moving from the open position to the closed positionadjacent the input end. Moving the first and second gripper members fromthe closed position to the open position causes the first and secondgripper members to disengage from the welding wire, the first and secondgripper members moving from the closed position to the open positionadjacent the output end.

The gripper assembly may include a guide device for moving the first andsecond gripper members from the closed position to the open position.The first and second roller chains may include a biasing member formoving the first and second gripper members from the open position tothe closed position.

BRIEF DESCRIPTION OF THE DRAWINGS

By way of example, specific embodiments of the disclosed device will nowbe described with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating an exemplary weldingarrangement including an exemplary wire feeder device according to thepresent disclosure;

FIG. 2 is a side, perspective view of the exemplary wire feeder deviceshown in FIG. 1;

FIG. 3 is a detail view of an exemplary gripper member used inconnection with the wire feeder device shown in FIG. 2;

FIG. 4A is a side view of an exemplary gripper member assembly havingfirst and second gripper members used in connection with the wire feederdevice shown in FIG. 2, the first and second gripper members beingorientated to apply a vertical pressure to a welding wire;

FIG. 4B is a front view of the exemplary gripper member assembly shownin FIG. 4A;

FIG. 4C is a front, perspective view of the exemplary gripper memberassembly shown in FIG. 4A, the gripper member assembly shown in a closedposition;

FIG. 4D is a perspective view of the exemplary gripper member assemblyshown in FIG. 4A, the gripper member assembly shown in an open position;

FIG. 5 is a side, perspective view of an alternate exemplary wire feederdevice according to the present disclosure;

FIG. 6 is an alternate perspective view of an exemplary gripper assemblyfor use in the wire feeder device of FIG. 5;

FIG. 7A is a perspective view of the gripper assembly shown in FIG. 6 inan opened position; and

FIG. 7B is a perspective view of the gripper assembly shown in FIG. 6 ina closed position.

DETAILED DESCRIPTION OF THE DISCLOSURE

A device in accordance with the present disclosure will now be describedmore fully hereinafter with reference to the accompanying drawings, inwhich preferred embodiments of the device are shown. The discloseddevice, however, may be embodied in many different forms and should notbe construed as being limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure will bethorough and complete, and will fully convey the scope of the device tothose skilled in the art. In the drawings, like numbers refer to likeelements throughout.

Referring to FIGS. 1-4D, an exemplary embodiment of a welding device 50incorporating a wire feeder device 100 for contacting and feeding awelding wire 60 (shown in FIG. 2) in accordance with the presentdisclosure is shown. While the present disclosure is illustrated anddescribed in terms of feeding a welding wire in a welding device, it iscontemplated that the present disclosure has applicability beyond thewelding industry and can be used in any industry where contacting andfeeding a longitudinal member is required.

Referring to FIG. 2, the wire feeder device 100 may include first andsecond gripper assemblies 110, 120 for contacting and feeding thewelding wire 60. As shown, the first and second gripper assemblies 110,120 may be orientated so that the second gripper assembly 120 is locatedabove the first gripper assembly 110, in a substantially coplanar orvertically adjacent orientation. In use, the first and second gripperassemblies 110, 120 may rotate in opposite directions so that the firstand second gripper members 200, 202 located on the first and secondgripper assemblies 110, 120, respectively, move from an open position toa closed position, and then, after traversing a substantially linearpath in the closed position, move from the closed position to the openposition, so that the first and second gripper members 200, 202 movevertically into and out of contact with respect to one another. That is,as the first and second gripper assemblies 110, 120 rotate in oppositedirections, the first and second gripper members 200, 202 come intocontact with one another (e.g., assuming a closed position), and engagethe welding wire 60 located therebetween, adjacent the input end 62 ofthe welding device 50. As the first and second gripper assemblies 110,120 rotate further, they disengage from each other (e.g., assuming anopen position), and thus disengage from the welding wire 60 adjacent theoutput end 64 of the device 100. In this manner, the first and secondgripper members 200, 202 grip the welding wire 60 therebetween andtranslate the wire along a substantially linear path. Because the firstand second gripper members 200, 202 are coupled to the rotating firstand second gripper assemblies 110, 120, respectively, the welding wire60 is thereby fed (e.g., moved) from the input end 62 to the output end64 of the welding device 50. As such, rotation of the first and secondgripper assemblies 110, 120 causes the welding wire 60 to be grippedbetween the first and second gripper members 200, 202, and for the firstand second gripper members 200, 202, along with the welding wire 60located therebetween, to move in the feed direction FD.

As the first and second gripper assemblies 110, 120 are substantiallysimilar, only the first gripper assembly 110 will be described indetail. It will be appreciated, however, that the second gripperassembly 112 may include any or all of the features described inrelation to the first gripper assembly 110, and thus, discussion of thesecond gripper assembly 120 will be omitted except for any distinctionsbetween the two (for example, differences in the configurations of thefirst and second gripper members 200, 202).

The first gripper assembly 110 may include a roller chain, an endlesstrack belt, a belt, or the like (collectively referred to herein as aroller chain 112). As shown, the roller chain 112 may be formed from aplurality of individual chain links 114 coupled together to be movablerelative to one another and to form an endless chain loop. In use, theroller chain 112 is rotationally coupled to first and second spacedsprockets 140, 142 arranged to rotate about parallel axes. As will beappreciated by persons of ordinary skill in the art, the sprockets 140,142 may be coupled to a motor (e.g., electric motor) so that in use, themotor drives or rotates the first and second sprockets 140, 142 in thesame direction (and at the same speed in the sprockets have the samediameter), which in turn rotates the roller chain 112 in the samedirection as the direction of rotation of the sprockets. As installed onthe first and second sprockets 140, 142, the roller chain 112 may assumea generally oval shape with parallel sides, although other shapes arecontemplated. In addition, although the illustrated embodiment includesa pair of sprockets, it is contemplated that more than two sprocketscould be used without departing from the scope of the disclosure. Theimportant point is that the gripping assemblies should be in contactmore than tangentially and, preferably, along as long a linear path asis practical to maximize the wire pulling force.

As shown, the first gripper assembly 110 may rotate in the clockwisedirection CW while the second gripper assembly 112 may rotate in thecounter-clockwise direction CCW. However, it should be appreciated thatthis is entirely optional, and the first gripper assembly 110 may rotatein the counter-clockwise direction CCW while the second gripper assembly112 may rotate in the clockwise direction CCW. In addition, while themotor has been described as rotating both the first and second sprockets140, 142, it is contemplated that the motor may only rotate one of thefirst and second sprockets, leaving the other sprocket to freewheel andbe driven by chain 112.

The first gripper assembly 110 may also incorporate one or more supports150 for supporting the roller chain 112 in the area in-between thesprockets 140, 142 and to assist the individual chain links 114 incoming together as the roller chain 112 rotates with the sprockets 140,142. The wire feeder device 100 may further incorporate a chaintensioner 160 to maintain the tension in the roller chain 112.

Referring to FIGS. 3-4D, the wire feeder device 100 may include firstand second opposing gripper members 200, 202. In use, the first grippermember 200 may be coupled to the first gripper assembly 110, while thesecond gripper member 202 may be coupled to the second gripper assembly120, although it is contemplated that this arrangement could bereversed. A first gripper member 200 may be coupled to each of the links114 of the first gripper assembly 110. Similarly, a second grippermember 202 may be coupled to each of the links 114 of the second gripperassembly 120.

In this manner, as the roller chain 112 of the first and second gripperassemblies 110, 120 rotates, the first and second gripper members 200,202 may move from an open position, in which opposing first and secondgripper members are spaced apart, to a closed position in which thefirst and second gripper members 200, 202 approach each other to therebysandwich the welding wire 60 therebetween. In the closed position thewelding wire 60 is gripped by opposing first and second gripper members200, 202 so that it is fed in the feeding direction FD. That is, as thefirst and second gripper assemblies 110, 120 rotate about theirrespective sprockets 140, 142, successive sequential pairs of first andsecond gripper members 200, 202 receive the welding wire 60 adjacent theinput end 62. As the first and second gripper assemblies 110, 120continue to rotate, opposing first and second gripper members 200, 202approach each other to clamp down onto the welding wire 60 disposedtherebetween. As the first and second gripper assemblies 110, 120continue to rotate, the first and second gripper members 200, 202 movein relatively linear manner along with the roller chains 112 of thefirst and second gripper assemblies 110, 120, and hence the first andsecond gripper members move, along with the welding wire 60 clampedtherebetween, toward the output end 64.

By pulling the welding wire 60 along using the first and second grippermembers 200, 202, which themselves are moving with the welding wire 60in the feeding direction FD, “shaving” of the wire is substantiallyreduced or eliminated because there is no relative movement or slippagebetween the feeder mechanisms (e.g., the first and second grippermembers 200, 202) and the welding wire 60.

As shown, the first and second gripper members 200, 202 have a lengthsubstantially corresponding to the length of each individual link 114.By using substantially rectangular shaped gripper members 200, 202,contact area between the gripper members 200, 202 and the welding wire60 is maximized as compared to prior wire feeders in which contact areais limited to a mutual tangent of adjacent circular feed rolls. Theincreased contact area decreases the contact pressure on the weldingwire 60 compared to the circular roller approach, which lowers thesurface pressure on the welding wire and thus decreases the risk ofdeforming the welding wire. While the gripper members 200, 202 have beenshown and described as having a substantially rectangularcross-sectional shape, virtually any other shape could be usedincluding, but not limited to, square, trapezoidal, etc.

The first and second gripper members 200, 202 may include a built-incentering function to center the position of the welding wire 60 (i.e.,to substantially align a centerline of the welding wire 60 with acenterline of the first and second gripper members 200, 202) to avoidthe risk of the wire tangling and to assist with feeding the weldingwire 60 through the welding device 50 without requiring a user to accessthe wire feeder device 100.

Referring to FIGS. 4A-4D, the first gripper member 200 may include anoutwardly extending member or projection 210 extending therefrom and acutout or recess 212 disposed directly adjacent the projection(collectively referred to herein as projection and cutout). The secondgripper member 202 (as shown in FIGS. 3-4D) may include a similarprojection 214 and cutout 216, though their positions are reversed. Whenthe gripping members are engaged, projections 210 and 214 arelongitudinally (i.e., along the length of wire 60) offset as shown inthe drawings wherein projection 201 is forward of projection 214. Inuse, when the first and second gripper members 200, 202 are configuredin the closed position, the projection 210 of the first gripper member200 is sized and adapted to be received within the cutout 216 of thesecond gripper member 202, while the projection 214 of the secondgripper member 202 is sized and adapted to be received within the cutout212 of the first gripper member 200. The projections 210, 214 arereceived in the cutouts 212, 216 and engage the welding wire 60therebetween.

To center the welding wire 60 between the first and second grippermembers 200, 202, the projections 210, 214 of the first and secondgripper members may also each include a notch 218 transversely centeredin their distal edges for receiving and contacting the welding wire 60.The notches 218 may be defined at the nadir intersection of twolaterally converging sides to cradle the welding wire betweenlongitudinally offset but adjacent notches. Alternatively the notch mayhave a semi-circular shape that more closely conforms to the roundshaped of the wire, although other shapes are contemplated. Thus, insome embodiments the projections 210, 214 may include sloped surfacesthat angle laterally from a high point at or adjacent an outer sidesurface 203 of the gripping members 200, 202 to a lower point at oradjacent a centerline of the first and second gripper members 200, 202.As such, the sloped surfaces facilitate positioning the welding wire 60towards the center of the first and second gripper members 200, 202. Thecombination of the sloped surfaces and notches 218 assist in centeringthe welding wire 60.

In use, the projections 210, 214, cutouts 212, 216 and notches 218assist with centering the welding wire 60 with respect to the grippermembers 200, 202, although any other centering mechanisms may beincorporated including, but not limited to, forming a longitudinalgroove in one of the gripper members, etc. Incorporating the built-incentering function eliminates the need for a user to open the mechanismin order to thread the welding wire 60. It may also ensure that the wiredoes not wander laterally within the feeding mechanism during operation.

The first and second gripper members 200, 202 may be made from anysuitable material. For example, the first and second gripper members200, 202 may be made from a flexible material such as, for example, anelastomer, Acrylonitrile butadiene styrene (ABS), Nylon 6, Nylon 6-6,Polyamides (PA), Polybutylene terephthalate (PBT), Polycarbonates (PC),Polyetheretherketone (PEEK), Polyetherketone (PEK), Polyethyleneterephthalate (PET), Polyimides, Polyoxymethylene plastic (POM/Acetal),Polyphenylene sulfide (PPS), Polyphenylene oxide (PPO), Polysulphone(PSU), Polytetrafluoroethylene (PTFE/Teflon), aluminum alloys, etc.

By making the first and second gripper members 200, 202 from a flexibleresilient material (i.e., one that is capable of deforming to conformitself to the shape of the welding wire), the same gripper members 200,202 may be used with different diameter welding wire 60. That is, bymaking the first and second gripper members 200, 202 from a flexibleresilient material, the first and second gripper members 200, 202 areable to better accommodate welding wires of various diameters therebyincorporating a level of built-in flexibility so that the same grippermembers 200, 202 can accept welding wire 60 of different diameters andavoid having the user replace the gripper members 200, 202 every time adifferent diameter welding wire 60 is used.

In addition, referring to FIG. 3, the first and second gripper members200, 202 may be coupled to each individual chain link 114 via one ormore biasing members 220 for providing a biasing force away from theindividual links 114. For example, as shown, the first and secondgripper members 200, 202 may be coupled to the individual chain links114 via a pair of springs 220 which bias the first and second grippermembers 200, 202 away from the roller chain 112 and toward each otherand hence toward the welding wire 60. Incorporation of the one or morebiasing members 220 further assists the wire feeder device 100 inaccommodating variable diameter welding wire 60 without having toreplace or change the first and second gripper members 200, 202, andeliminates the need for a user to have to set the mechanism for aspecific diameter of welding wire 60. That is, by incorporating one ormore biasing members 220, the wire feeder device 100 is better able toaccommodate welding wire 60 having various diameters. In addition, byincorporating one or more biasing members 220, the wire feeder device100 is better able to provide increased grip pressure as generallyneeded for larger diameter welding wire. The first and second grippermembers 200, 202 may be coupled to the biasing member 220 eitherdirectly, or indirectly via an intermediate member 206.

As described, the wire feeder device 100 can feed (e.g., move) thewelding wire 60 from the input end 62 to the output end 64 throughrotation of the sprockets 140, 142 and attendant movement of theindividual gripper members 200, 202. The contact pressure applied by thegripper members 200, 202 to the welding wire 60 can be controlled bycontrolling the spacing distance between the rotating sprockets 140, 142and the flexibility of the gripper members 200, 202, as well as bycontrolling the spring constant of the one or more biasing members 220coupling the gripper members 200, 202 to the individual chain links 114.In some embodiments, the roller chain 112 may be supported in a mannerthat maintains a consistent desired pressure on the welding wire 60 byensuring that a constant distance is maintained between the rollerchains 112.

In some embodiments, the welding wire 60 is centered by thecorresponding shapes of the opposing gripper members 200, 202, such asby incorporating corresponding projections 210, 214, cutouts 212, 216and notches 218. As a result, the welding wire 60 may be fed through thewire feeding device 100 by inserting the welding wire 60 into the inputend 62. The welding wire 60 may be automatically centered and drawnbetween the opposing gripper members 200, 202 such that opening andaccessing the wire feeding device 100 is not required.

By utilizing larger gripper members 200, 202, and by feeding the weldingwire 60 by pulling it with the gripper members as they move in thefeeding direction FD, a larger contact surface area between the weldingwire 60 and the wire feeder device 100 may be created, resulting indecreased required contact pressure on the welding wire 60. This lowersurface pressure decreases the risk of deforming the welding wire 60. Inaddition, as there is no relative movement or slippage between thegripper members 200, 202 and the welding wire 60 being fed, thedisclosed arrangement substantially eliminates any risk of “shaving” ofthe welding wire.

Referring now to FIGS. 5 through 7B, an alternate exemplary embodimentof a wire feeder device 500 for use in a welding device 50 forcontacting and feeding (e.g., moving) the welding wire 60 in accordancewith the present disclosure is shown. The wire feeder device 500 of thisembodiment is similar in operation to the wire feeder device 100previously described except as described herein. However, instead of twogripping assemblies being coplanar or vertically adjacent as in feederdevice 100, in device 500 the single gripping assembly has two sets oflaterally adjacent gripping members that engage laterally rather thanvertically.

More specifically, the wire feeder device 500 may include a singlegripper assembly 510 for contacting and feeding the welding wire 60 in afeeding direction FD (FIG. 6). The gripper assembly 510 may include aroller chain 512 associated with first and second sprockets 540, 542 sothat rotation of the sprockets 540, 542 rotates the roller chain 512,which in turn causes first and second lateral gripper members 520, 530to move laterally from an open position (FIG. 7A) to a closed position(FIG. 7B), and eventually from the closed position back to the openposition, so that the first and second lateral gripper members 520, 530may come into and out of contact with a welding wire 60 disposedtherebetween. That is, as the roller chain 512 rotates (e.g., via amotor 75, which rotates first and second sprockets 540, 542), forexample, in the clockwise direction, the first and second lateralgripper members 520, 530 move from an open position (in which the firstand second lateral gripper members 520, 530 are spaced laterally apartfrom one another) to a closed position (in which the first and secondlateral gripper members come into contact with the welding wire 60located therebetween). As can best be seen in FIG. 6, the first andsecond lateral gripper members 520, 530 are configured in the openposition adjacent the input end 62, and move from the open position tothe closed position when in the central portion of the wire feederdevice 500. As they near the output end 64 the first and second lateralgripper members 520, 530 come out of contact with one another (againassuming the open position), and release the welding wire 60, adjacentthe output end 64. In this manner, the gripper members 520, 530laterally grip the welding wire 60 therebetween and because the firstand second gripper members 520, 530 are coupled to the rotating rollerchain 512 of the gripper assembly 510, the welding wire 60 is fed (e.g.,moved) from the input end 62 to the output end 64 of the welding device500.

Thus, as arranged, movement of the gripper assemblies 510 causes thewelding wire 60 to be gripped between the first and second lateralengaging gripper members 520, 530, and the first and second grippermembers 520, 530 and the welding wire move in the feed direction FD. Byutilizing a single gripper assembly 510 with laterally contactinggripper members 520, 530 the wire feeder device 500 minimizes the numberof parts required and hence saves space.

The gripper assembly 510 may include a roller chain, an endless trackbelt, a belt, or the like (collectively referred to herein as a rollerchain 512). As shown, the roller chain 512 may be formed from aplurality of individual chain links 514 coupled together to form achain. In use, the roller chain 512 may be coupled to first and secondsprockets 540, 542 so that as the sprockets rotate, roller chain 512 ismoved in a corresponding direction. As will be appreciated by one ofordinary skill in the art, the sprockets 540, 542 may be coupled to amotor 75 (e.g., electric motor) so that in use, the motor drives orrotates the first and second sprockets 540, 542, which in turn rotatesthe roller chain 512, and the first and second gripper members 520, 530.The gripper assembly 510 may assume a generally oval shape, althoughother shapes are contemplated. In addition, although the illustratedembodiment includes a pair of sprockets, it is contemplated that morethan two sprockets could be used without departing from the scope of thedisclosure.

As shown, the gripper assembly 510 may rotate in the clockwise directionCW. However, it should be appreciated that this is entirely optionallyand that the gripper assembly 510 may rotate in the counter-clockwisedirection CCW. In addition, while the motor 75 has been described asrotating both the first and second sprockets 540, 542, it iscontemplated that the motor 75 may only rotate one of the first andsecond sprockets, leaving the other sprocket to freewheel.

The wire feeder device 500 may also include first and second grippermembers 520, 530 that are associated with the roller chain 512. Thefirst and second gripper members 520, 530 being arranged in a side byside relationship.

As shown, the first and second gripper members 520, 530 are arranged ina lateral, side by side relationship so that rotation of the rollerchains 512 causes the first and second gripper members 520, 530 to movefrom an open position (in which the first and second gripper members520, 530 are spaced apart) to a closed position so that the first andsecond gripper members 520, 530 laterally approach each other tosandwich the welding wire 60 therebetween. As such, the welding wire 60is gripped and fed in the feeding direction FD. That is, as the rollerchains 512 rotates, the first and second gripper members 520, 530 movefrom the open position adjacent the input end 62 to the closed position(adjacent the central portion of the wire feeder device 500) to receivethe welding wire 60 and clamp it therebetween. As the roller chain 512continues to rotate, the first and second gripper members 520, 530 movealong with the roller chain 512 clamped therebetween, and hence thefirst and second gripper members move the welding wire 60 toward theoutput end 64. By pulling the welding wire 60 along using the first andsecond gripper members 520, 530, which themselves are moving along withthe welding wire 60 in the feeding direction FD, “shaving” of the wireis substantially reduced or eliminated because there is no relativemovement or slippage between the feeder mechanisms (e.g., the gripperassembly 510) and the welding wire 60.

The gripper assembly 510 may also include a guide rail, cam, bracket,etc. 550 (collectively “guide device”) at or before the input end 62 andthe output end 64 that together cause the first and second grippermembers 520, 530 to laterally open (e.g., move from the closed positionto the open position) so that the welding wire 60 may be received andreleased, respectively, with respect to the first and second grippermembers 520, 530. As best shown in FIG. 6, which illustrates the gripperassembly 510 with a cover 511 removed, the guide device 550 may be inthe form of a sloped ram that contacts the first and second grippermembers 520, 530 as they are rotated, causing the first and secondgripper members 520, 530 to separate (e.g., spread apart, separate,etc.). As shown, the gripper assembly 510 may include guide devices 550on either side of the first and second sprockets 540, 542.

Referring to FIGS. 7A and 7B, the first and second gripper members 520,530 may include a plurality of biasing members 560, such as, forexample, springs, to bias the first and second gripper members 520, 530into contact with one another and thus into contact with the weldingwire 60 located therebetween (e.g., to bias the first and second grippermembers 520, 530 from the open position to the closed position). In use,the biasing members 560 may be orientated about one or more rods 562associated with the first and second gripper members 520, 530 to biasthe first and second gripper members 520, 530 to the closed position. Assuch, in use, as soon as the first and second gripper members 520, 530rotate beyond the guide devices 550, the biasing member 560 causes thefirst and second gripper members 520, 530 to close. In use, the guidedevice 550 may extend to a sufficient distance so that when the guidedevices 550 stop, the welding wire 60 is located in-between the firstand second gripper members 520, 530.

Alternatively, it is envisioned that the plurality of biasing members560 may be used to bias the first and second gripper members 520, 530 tothe opened position and that a cam or other similar device may be usedto move the first and second gripper members 520, 530 to the closedposition.

Incorporation of the biasing member 560 also assists the wire feederdevice 500 in accommodating variable diameter welding wire 60 withouthaving to replace the gripper members 520, 530 and also eliminates theneed for a user to adjust the device to accommodate a specific diameterof welding wire 60. In addition, by incorporating one or more biasingmembers 560, the wire feeder device 500 is better able to provideincreased grip pressure as generally needed for lager diameter weldingwire.

The first and second gripper members 520, 530 may be substantiallysimilar to the first and second gripper members 200, 202 previouslydescribed in that, similar to the gripper members 200, 202, the firstand second gripper members 520, 530 may have a length substantiallycorresponding to the length of each individual link 514. By usingsubstantially rectangular shaped gripper members 520, 530, the contactarea between the gripper members 520, 530 and the welding wire 60 can bemaximized, which in turn may decrease the contact pressure on thewelding wire 60. Decreased contact pressure reduces the likelihood thatthe welding wire 60 will be deformed or damages in some way. While thegripper members 520, 530 have been shown and described as having asubstantially rectangular shape, virtually any other shape could be usedincluding, but not limited to, square, trapezoidal, etc.

In addition, the first and second gripper members 520, 530 may include abuilt-in centering function to center the position of the welding wire60 (e.g., to substantially align a centerline of the welding wire 60with a centerline of the first and second gripper members 520, 530) toavoid the risk of tangling and to assist with feeding the welding wire60 through the wire feeder device 500 without having a user accessingthe wire feeder device 500. That is, as previously described, the firstgripper member 520 may include a projection 210 extending therefrom anda cutout 212. The second gripper member 530 may include a similarprojection 214 and cutout 216. In use, the projection 210 of the firstgripper member 520 is sized and adapted to be received within the cutout216 of the second gripper member 530, while the projection 214 of thesecond gripper member 530 is sized and adapted to be received within thecutout 212 of the first gripper member 520. The projections 210, 214interconnect with the cutouts 212, 216 to receive the welding wire 60therebetween. The projections 210, 214 may also include a notch 218 atthe tip thereof for receiving and contacting the welding wire 60. Thenotch 218 may include a semi-circular shape, although other shapes areenvisioned. The projections 210, 214 may include a sloped surface thatangles from a high point at or adjacent an outer side surface 203thereof to a lower point at or adjacent a centerline of the first andsecond gripper members 520, 530. As such, the sloped surface facilitatespositioning the welding wire 60 towards the center of the first andsecond gripper members 520, 530. The combination of the sloped surfacesand notches 218 assist centering the welding wire 60.

In use, the projections 210, 214, cutouts 212, 216, and notch 218 assistwith centering the welding wire 60 with respect to the gripper members520, 530, although any other centering mechanisms may be incorporatedincluding, but not limited to, forming a longitudinal groove in one ormore of the gripper members, etc. Incorporating the built-in centeringfunction eliminates the need for a user to open the mechanism in orderto thread the welding wire 60.

As previously described, the first and second gripper members 520, 530may be made from any suitable material. For example, the first andsecond gripper members 520, 530 may be made from a flexible materialsuch as, for example, an elastomer, or any of the other as mentionedmaterials. By making the first and second gripper members 520, 530 froma flexible material (i.e., one that is capable of deforming to conformitself to the shape of the welding wire), the same gripper members 520,530 can be used with different diameter welding wires 60. That is, bymaking the first and second gripper members 520, 530 from a flexiblematerial, the first and second gripper members 520, 530 are able tobetter accommodate welding wires of various diameters therebyincorporating a level of built-in flexibility so that the same grippermembers 520, 530 can accept welding wire 60 of different diameters andavoid having the user replace the gripper members 520, 530 every time adifferent diameter welding wire 60 is used.

The gripper assembly 510 may also incorporate one or more supports 580for supporting the roller chain 512 in the area in-between the sprockets540, 542.

The wire feeder device 500 may also incorporate a chain tensioner tomaintain the tension in the roller chain 512.

According to the wire feeder device 500 of the present disclosure, inuse, feeding the welding wire 60 is created by rotation of the sprockets540, 542 via the motor 75. The contact pressure to the welding wire 60is applied by the flexibility of the gripper members 520, 530 to adaptto various diameters of the welding wire 60.

The welding wire 60 is also centered by the corresponding shapes of thegripper members 520, 530 (e.g., incorporation of correspondingprojections 210, 214, cutouts 212, 216 and notches 218). As a result,the welding wire 60 made be fed through the wire feeding device 500 byinserting the welding wire 60 into the input end 62. The welding wire 60may be automatically centered and drawn between the opposing grippermembers 520, 530 such that opening and accessing the wire feeding device500 is not required.

By utilizing larger gripper members 520, 530, and by feeding the weldingwire 60 by pulling it with gripper members 520, 530 as they move in thefeeding direction FD, a larger contact surface area between the weldingwire 60 and the wire feeder device 500 may be created, resulting indecreased contact pressure on the welding wire 60. This lower surfacepressure decreases the risk of deforming the welding wire 60. Inaddition, as there is no relative movement or slippage between thegripper members 520, 530 and the welding wire 60 being feed, thedisclosed arrangement substantially eliminates any risk of “shaving” ofthe welding wire.

As noted above, since the projection of each gripper member is receivedin the cutout of the other gripper member, the notches formed in firstand second gripper members are longitudinally offset such that theycontact the welding wire at different but longitudinally adjacent pointsalong the wire. This offset minimizes compression and potentialdistortion of the welding wire.

In addition to the described structural aspects of the presentinvention, a method of feeding welding wire according to the presentinvention comprises the steps of: positioning first and secondsequentially arranged endless loops of gripping members in closeadjacency such that the gripping members of the first loop engage thegripping members of the second loop in a substantially linear path alongportions of the lengths of the loops; disposing and laterally centeringthe welding wire between said loops of gripping members such thatlateral movement of the welding wire is prevented by the engagedgripping members; rotating the loops such that different length sectionsof each loop sequentially come into engagement and move the welding wirealong said substantially linear path. In addition, the method includesthreading the welding wire between the gripping members by startingrotation of the loops and pushing the wire between the moving grippingmembers without separating the loops of gripping members. The step ofcentering is achieved by the inherent structure of the gripping members.

As used herein, an element or step recited in the singular and proceededwith the word “a” or “an” should be understood as not excluding pluralelements or steps, unless such exclusion is explicitly recited.Furthermore, references to “one embodiment” of the present invention arenot intended to be interpreted as excluding the existence of additionalembodiments that also incorporate the recited features. In addition, forthe sake of convenience and clarity, terms such as “front”, “rear”,“top”, “bottom”, “upper”, “lower”, “vertical”, “horizontal”, “lateral”,“longitudinal”, “transverse”, “height”, and “width” may have been usedherein to describe the relative placement and orientation of the deviceand its various components, each with respect to the geometry andorientation of the device as it appears in the figures. Theseorientation and placement descriptors are used for convenience indescribing the embodiments and are not intended to be limiting on thescope of the invention unless otherwise apparent in the claims.

While certain embodiments of the disclosure have been described herein,it is not intended that the disclosure be limited thereto, as it isintended that the disclosure be as broad in scope as the art will allowand that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

What is claimed is:
 1. A method for feeding a welding wire comprising:positioning first and second endless loops of sequentially arrangedgripper members in close adjacency; counter rotating said loops suchthat successive gripper members of the first loop engage successivegripper members of the second loop along a substantially linearengagement path at successive respective length portions of the rotatingloops; inserting the welding wire between said loops of gripper members;engaging the inserted welding wire by and between engaged grippermembers and pushing the engaged welding wire along said engagement path;laterally centering the welding wire between said loops of grippermembers such that lateral movement of the welding wire is impeded byengaged gripper members; and longitudinally offsetting engaged grippermembers along said engagement path such that the engaged gripper memberscontact the welding wire at different but longitudinally adjacent pointsalong the wire to minimize compression and distortion of the wire. 2.The method of claim 1 further comprising: receiving in a recess definedin each gripper member a projection from its engaged gripper member; andcontacting the welding wire with the projections from the engagedgripper members along the engagement path.
 3. The method of claim 1further comprising: receiving in a recess defined in each gripper membera projection from its engaged gripper member; and contacting the weldingwire in notches defined in the distal edges of the engaged grippermembers along the engagement path.
 4. The method of claim 3 whereininserting the welding wire includes threading the welding wire betweenthe gripper members at an input end of said path without separating theloops of gripper members along said path,.
 5. The method of claim 4wherein laterally centering the welding wire is effected by thestructures and relative positioning of the gripper members and orientsthe welding wire substantially parallel to said substantially linearpath.
 6. The method of claim 5 further comprising resiliently conformingthe distal edges of the engaged gripper members to the shape of thewelding wire along said engagement path.
 7. The method of claim 6further comprising positionally biasing said each gripper member towardits engaged gripper member along said path to firmly engage the weldingwire therebetween.
 8. The method of claim 3 further comprisingresiliently conforming the distal edges of the engaged gripper membersto the shape of the welding wire along said engagement path.
 9. Themethod of claim 3 further comprising positionally biasing said eachgripper member toward its engaged gripper member along said path tofirmly engage the welding wire therebetween.
 10. A method for feeding awelding wire comprising: positioning first and second endless loops ofsequentially arranged gripper members in close adjacency; counterrotating said loops such that successive gripper members of the firstloop engage successive gripper members of the second loop along asubstantially linear engagement path at successive respective lengthportions of the rotating loops; inserting the welding wire between saidloops of gripper members; engaging the inserted welding wire by andbetween engaged gripper members and pushing the engaged welding wirealong said engagement path; laterally centering the welding wire betweensaid loops of gripper members such that lateral movement of the weldingwire is impeded by engaged gripper members; receiving in a recessdefined in each gripper member a projection from its engaged grippermember; and contacting the welding wire with the projections from theengaged gripper members along the engagement path.
 11. The method ofclaim 10 wherein contacting the welding wire is effected in notchesdefined in the distal edges of the engaged gripper members.
 12. Themethod of claim 10 further comprising resiliently conforming the distaledges of the engaged gripper members to the shape of the welding wirealong said engagement path.
 13. The method of claim 12 furthercomprising positionally biasing said each gripper member toward itsengaged gripper member along said path to firmly engage the welding wiretherebetween.
 14. A method for feeding a welding wire comprising:positioning first and second endless loops of sequentially arrangedgripper members in close adjacency; counter rotating said loops suchthat successive gripper members of the first loop engage successivegripper members of the second loop along a substantially linearengagement path at successive respective length portions of the rotatingloops; inserting the welding wire between said loops of gripper members;engaging the inserted welding wire by and between engaged grippermembers and pushing the engaged welding wire along said engagement path;laterally centering the welding wire between said loops of grippermembers such that lateral movement of the welding wire is impeded byengaged gripper members; receiving in a recess defined in each grippermember a projection from its engaged gripper member; contacting thewelding wire with the projections from the engaged gripper members alongthe engagement path; and resiliently conforming the distal edges of theprojections of engaged gripper members to the shape of the welding wirealong said engagement path.
 15. The method of claim 14 furthercomprising positionally biasing said each gripper member toward itsengaged gripper member along said path to firmly engage the welding wiretherebetween.